I think we need to seriously discuss all the splicing/grouping/etc. stuff.  
Those decisions will affect everything else, and there are complex trade-offs.  
One challenge is that practically any character or character pair seems to be 
already used by someone.

> proposal 3:
> 3.  . = SPLICE = GROUP, remove SPLICE-at-the-eol rule (this helps
> justify removing the SPLICE-at-the-eol: since \ at the eol has an
> existing meaning in other languages, we avoid it.  Incidentally, "."
> has a meaning in general western written languages: it ends sentences.
>  So we could justify using it to mean "end the expression so far and
> start a new expression", which is one interpretation of the
> SPLICE-inline rule.)

Claiming "." as the "end of expression" is an interesting idea, but I don't 
think it is a good idea for Lisps.  The problem is that "." already has a (very 
old) meaning; it precedes the cdr of a pair. E.G., (a . b).  In cases where it 
makes sense, it'd be wise for the same operator to have the same meaning, or 
it's pretty confusing.

I would expect during indentation processing that:
a . b
would mean the same as:
(a . b)

Thus, I don't think the following works well:
> foo
>   :foo-stuff . exp1()
>   :bar-stuff . call the function
because I think a reader would expect this to mean:
(foo (:foo-stuff . (exp1)) (:bar-stuff . call...))

I don't know of a Lisp spec that defines (. stuff), but interestingly, in 
practice, that usually evaluates (in the reader) as just "stuff" because of the 
way that the Lisp readers are interpreted.  I'm fine with mandating that, if 
that helps; it creates an escape we can use.

So I don't like the idea of "." as "splice"; I think it's too confusing.

> let
>   .
>     a b
>     c d
>   e

This one doesn't look bad; claiming that "." on a line by itself as a special 
case seems plausible.  I'm still worried that "." is too hard to see, but it 
*is* plausible as a "group" marker.

--- David A. Wheeler

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